Polyazo-dyestuffs



United States Patent ()fifl 2,897,188

Patented July 28, 1959 1 2 2,897,188 Example 1 POLYAZO DYESTUFFS Thediazo-compound obtained by diazotizing 46.4 parts v of4-amino-4'-nitrodiphenylamine-2'-sulfonic acid is ad- Josef g Frankfurtam and Helm"! G169, justed to a pH-va1ue of 10.5 with a sodium hydroxideHofheim (Tatum), Germany Farblvel'ke 5 solution of 33% strength and thencombined with an Hoechst Aktrengesellschaftwormals Merster Lucius &alkaline solution of 201 parts of 3 s, dihydmxydiphenyl Bmnmg hankfurtam Germany famine. A diazo-solution prepared from 18.6 parts of NoDrawing. Application November 21, 1957 V aniline is added to thedyestuft so obtained and sodium Sena] No. 697,812 i carbonate is admixedso that the pH-value does not fall I below 8. The coupling occursrapidly. The mixture is C g. i3 y stirred for a further 4 hours and thedyestuif is separated .by the addition of sodium chloride. It dyesleather 6 Clalmsbeautiful yellow-brown tints of good fastnessproperties.

The present invention relates to new polyazo-dyestufis, v 1 Example 2more particularly it relates to azo-dyestufis corresponding 30.9 partsof 4-amino-4-nitrodiphenylamine-2'-sulfonic to the following generalformula: acid are diazotized in the usual manner and the diazo- 0H z 0H1 X X f wherein one X stands for hydrogen and the other X compound soobtained is combined with an alkaline stands for the sulfonic acidgroup, Y represents hydrogen, .1 solution of 20.1 parts of3,3'-dihydroxydiphenylamine. a nitro or acetylamino group, Z stands forhydrogen or The dyestuif so obtained is then coupled with the diazothegroup N=NR Z stands for hydrogen or the V tized suspension of 34.6 partsof 1-aminobenzene-4-sulgroup N=NR and R R R and R represent arofonicacid, sodium carbonate being added so that the pH- matic radicals. Ivalue does not fall below 8. The mixture is stirred for a We have foundthat valuable brown polyazo-dyest'ufl's further 4 hours and the dyestuifis precipitated by the are obtained by coupling 1 mol of3,3-dihydroxydiaddition of sodium chloride. It dyes leather beautifulphenylamine with at least 1 mol of a diazotized aminobrown tints and hasa very good levelling power. The diphenylamine sulfonic acid which maybe substituted by 40 dyestufi corresponds to the following formula:

HO OH nitro or acetylarnino groups, and, if desired, with up to V v m's, 4 mols of any diam-compound.

The new dyestuffs are especially suitable for dyeing P i d p y -Q allkinds of leather. The brown tints obtained are disacld are dlazot zed lnthe usual ma r, h (11320-00111- tinguished by a good fastness to light,to washing and ro s p t 1 d to a p -v of 1 -5 to perspiration. The goodlevelling power of the new with a sodium hydroxlde solution of 33%strength and dyestufis is especially valuable when glove leather isdyed. then Combined w an ka lut on of 20:1 Parts Of In spite of a verygood solubility of the dyestufis the ,3'- y Y P Y1 e, A 1aZ0S0l}1t10nprepare d dyebaths are exhausted even in the presence of small rom 173parts of 1-amino-2-chloro-4-n trobenzene s quantities of an acid. Theseproperties render therdyeadded to the dyestuif so obtained and sodiumcarbonate stuffs-especially suitable for brush dyeing. is admixedrsothat the pH-value does not fall below 8.

The following examples illustrate the invention, but 7 Thetetrakisazo-dyestuff is rap dly formed. The mixthey are not intended tolimit it thereto, the parts being ture is stirred for a further .4 hoursand the dyestuff is by weight. separated by the addition of sodiumchloride. It dyes leather medium brown tints. The dyestuif correspondsto the following formula:

the dyestutf is separated After filtering and HO OH N II N N ]Cl NH N:

Example 4 92.7 parts of 4-amino-4-nitrodiphenylamine-2-sulfonic acid arediazotized in the usual manner, the diazo-compound is adjusted to apH-value of 10.5 with a sodium hydroxide solution of 33% strength andthen combined with an alkaline solution of 20.1 parts of3,3-dihydroxydiphenylamine. The dyestuff so obtained is then coupleddrying, a black-brown powder is obtained which is'readiIy soluble inwater. The dyestutf dyes leather deep brown tints of a good fastness tolight. The levelling power and the fastness to perspiration of thedyestufi are especially good. The dyestufl? can be used with specialadvantage for brush dyeing owing to its good solubility. It correspondsto the following formula:

HO OH with the diazotized suspension of 21.8 parts of l-amino4-nitrobenzene-2-sulfonic acid, sodium carbonate being; added so thatthe pH-value does not fall below 8. The mixture is stirred for a further4 hours and the dyestutf is precipitated by the addition of sodiumchloride. It dyes leather covered brown tints and has a good levellingpower.

Example 5 26.4 parts of 4-aminodiphenylamine-Z-sulfonic acid arediazotized in the usual manner. The diazo-suspension obtained is causedto run into an alkaline solution of 20.1 parts of3,3-dihydroxydiphenylamine and a sodium hydroxide solution is'added sothat the pH-value does not fall below 9. When traces of diazo-cornpoundcan no longer be detected, a diazo-suspension prepared by diazotizing61.8 parts of 4-amino-4 -nitrodiphenylamine-2-su]fonic acidis added atthe same pH-value. The trisazo-dyestufi? is rapidly formed. The mixtureis When in the above example 61.8 parts of 4-amino-4-nitrodiphenylamine-Z'-sulfonic acid are replaced by a mixture of 30.9parts of 4-amino-4-nitrodiphenylamine-2'- sulfonic acid and 26.4 partsof 4-aminodiphenylamine-2- sulfonic acid, a dyestufi is obtained whichhas simil properties but a somewhat deeper tint.

Example 6 Q It dyes leather brown tints with a violet hue. stutfcorresponds to the following formula:

The dyehydroxide solution of 33% strength and then combined with analkaline solution of 20.1 parts of 3,3-dihydroxy- HO 7 I OH OgH IIT S03H Example 7 92.7 parts of 4-amino-4'-nitrodiphenylamine-2'-su1fonicacid are diazotized in the usual manner, the diazo-compound is adjustedto a pH-value of 10.5 with a sodium hydroxide solution of 33% strengthand then combined with an alkaline solution of 20.1 parts of3,3'-dihydroxydiphenylamine. The dyestuff so obtained is admixed withthe tetrazo-solution prepared from 14 parts of 4,4-diaminodiphenylamine-Z-sulfonic acid and sodium carbonate is added sothat the pH-value does not fall below 8-. The mixture is stirred for afurther 4 hours and the dyestufi is separated by the addition of sodiumchloride. It dyes leather deep brown tints and has a good levellingpower.

In the above example 0.05 mol of the tetrazo-compound is used per 0.1mol of the trisazo-dyestuif which is transformed into theoctakisazo-dyestufi.

Example 8 The diazo-compound obtained by diazotizing 135 partsdiphenylamine. After stirring for 4 hoursthe coupling solutionis'adju'ste'd to apH-value of 8 with hydrochloric acid and the dyestufI"is precipitated by the addition-of sodium chloride. It dyes leatherred-brown tints of good covering properties.

Example 1 The diazo-compound obtained by diazotizing 144.4 parts of4-amino-4-acetylamino-diphenylamine-Z-sulfonic acid is adjusted to apH-value of 10.5 with a sodium hydroxide solution of 33% strength andthen combined with an alkaline solution of 20.1 parts of3,3'-dihydroxydiphenylamine. After stirring for 4 hours the solution isadjusted to a pH-value of 8 with hydrochloric acid and the dyestufl? isseparated by the addition of sodium chlo- It'dyes leather brown tintsand has a very good levelling power.

We claim:

1. The polyayzo-dyestufls corresponding to the following generalvformula:

OH z OH E Z; X

.wherein on e X stands for hydrogen and the other X smiles forthesulfonicacid'group, Y represents a member selected from the groupconsisting of hydrogen, nitro and acetylamino, Z stands for a memberselected from the group consisting of hydrogen and the group N=NR Zstands for a member selected from the group consisting of hydrogen andthe group N=NR R and R represent members selected from the groupconsisting of radicals of the benzene and diphenylamine series, R repre-Example 9 135 parts of 4-amino-2'-nitrodiphenylamine-4-sulfonic acid arediazotized in known manner, the diazo-comsents a radical of thediphenylamine series and R represents a member selected from the groupconsisting of radicals of the benzene, naphthalene and diphenylaminepound is adjusted to a pH-value of 10.5 with a sodium series.

2,897,188 7 i 8 2. The polyazo-dyestuff corrggponding to the following fV V lmnl a:

HO 0H E 0&1:

3. The polyazo-djlestufi corresponding to the following formula: V

' HO OH sum 7 N 1 1 i V -SQaE l l r r V NH N O: $40.1:

4. The polyazordyestufi corresponding to the following formula:

7 HO OH v a IIIT v l V v 01H '7 v SO H 9 10 5. The polyazo-dyestuficorresponding to the following formula:

HO OH SOQH In! N S0311 6. The polyazo-dyestufi corresponding to thefollowing formula:

References Cited in the file of this patent UNITED STATES PATENTS2,276,169 Dobler, et a1. Mar. 10, 1942 2,750,375 Siebert et a1 June 12,1956 2,777,838 Huss et a1 Jan. 15, 1957

1. THE POLYAYZO-DYESTUFFS CORRESPONDING TO THE FOLLOWING GENERALFORMULA: